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Ting-Kai Leung

Publications and source records attributed to Ting-Kai Leung.

13 recordsLinked to original sources
PubMed2006

Release properties on gelatin-gum arabic microcapsules containing camphor oil with added polystyrene.

In this study, gelatin blended with arabic gum microcapsules containing camphor oil with added polystyrene were fabricated by a compound coacervation method. The parameters of oil/wall volume ratio, emulsification stirring speed, concentration of cross-linking agent, treated time and oil release properties were investigated. In order to improve the constant release effect of camphor oil, oil-soluble polystyrene (PS) was used as a sustained release agent. The camphor oil release curves were expressed by the exponential equation: psi(t)=C(eq)(1-e(-t/tau)), where psi(t) represent the variant of camphor oil concentration in the operation environment, C(eq) as the equilibrium state, t as the release time and tau as time constant. C(eq) and tau are significant factors pertaining to the camphor oil release properties. The results indicated that, for the microcapsules, the optimal oil/wall volume ratio was 0.75 to achieve the encapsulation efficiency of 99.6 wt.%. The average particle size were 294.7+/-14.2 microm, 167.2+/-11.2 microm, 85.7+/-8.7 microm at the homogenization stirring speed of 500, 1000, and 2000 rpm, respectively. The effect of sustained oil release will increase whereas the stirring speed decreases and the concentration of glutaraldehyde (GA) and treated time increases. Along with the increasing of quantity of polystyrene added, C(eq) decreased and tau increased, indicating that the sustained oil release amount and the release rate depend on the quantity of PS considerably.

Biocompatible Materials↗
PubMed2006

Differential diagnosis of cystic lymphangioma of the pancreas based on imaging features.

Lymphangioma is a benign tumor, which is a consequence of lymphatic malformation with blockage of lymphatic flow. Most lymphangiomas occur in the neck and axillary region, and < 1% occur in the mesentery or retroperitoneum. Lymphangiomas arising from the pancreas are extremely rare. We report the case of a 34-year-old woman with cystic lymphangioma of the pancreas without major symptoms or signs. A 6 x 6 cm intra-abdominal cystic mass was incidentally revealed by sonography during a health examination. It is always a challenge to differentiate the lesion from other possible cystic-like pancreatic neoplasms. Differential diagnosis of cystic lymphangioma from other cystic-like tumors of the pancreas can be performed based on their imaging characteristics, including presence of septa, cystic or wall calcification, soft tissue, wall thickness, single or multiple loculation, and dilatation of the pancreatic duct. Post-gadolinium magnetic resonance imaging is excellent in defining the origin of intra-abdominal cystic mass and intracystic septa.

Adult↗
PubMed2006

Retrospective study of the total insertion period of peripherally inserted central catheter: discussion of anti-thrombogenic surface and other biomaterial requirements.

A retrospective study of patients' records on reviewing the purpose of venous catheter insertion (chemotherapy, blood transfusion, antibiotics or parenteral nutrition); total period of insertion; reason for catheter removal. 120 admitted patients who received fluoroscopic guide PICC (4-French single lumen silicone rubber catheter) insertions into distal SVC via antecubital region of forearm. We retrospectively review human factors including the patients' laboratory data of pre- and post-insertion, total insertion period and reasons for withdrawal. The important human factors that affect the clinical outcome of PICC were also evaluated. The results indicated that the most common complications were wound oozing, phlebitis, occlusion, infection and leaking. Persistent wound oozing for over 3-day-period is the higher incidence of complication. It also demonstrated a surprisingly high ratio (> 77%) in those patients with thrombocytopenia and leukemia. In this group, persistent low platelet counts could be noted, the ratio of failure (remove PICC within 3 days) is 10% and there is 40% decrease insertion period (< 30 days). Prospectively, it is worthwhile to choose new material or new technology of surface coating of PICC, to decrease consumption of platelet thrombogenic proteins and to maintain normal coagulate function of human bodies.

Catheterization, Central Venous↗
PubMed2005

Balthazar computed tomography severity index is superior to Ranson criteria and APACHE II scoring system in predicting acute pancreatitis outcome.

AIM: Acute pancreatitis (AP) is a process with variable involvement of regional tissues or organ systems. Multifactorial scales included the Ranson, Acute Physiology and Chronic Health Evaluation (APACHE II) systems and Balthazar computed tomography severity index (CTSI). The purpose of this review study was to assess the accuracy of CTSI, Ranson score, and APACHE II score in course and outcome prediction of AP. METHODS: We reviewed 121 patients who underwent helical CT within 48 h after onset of symptoms of a first episode of AP between 1999 and 2003. Fourteen inappropriate subjects were excluded; we reviewed the 107 contrast-enhanced CT images to calculate the CTSI. We also reviewed their Ranson and APACHE II score. In addition, complications, duration of hospitalization, mortality rate, and other pathology history also were our comparison parameters. RESULTS: We classified 85 patients (79%) as having mild AP (CTSI <5) and 22 patients (21%) as having severe AP (CTSI > or =5). In mild group, the mean APACHE II score and Ranson score was 8.6+/-1.9 and 2.4+/-1.2, and those of severe group was 10.2+/-2.1 and 3.1+/-0.8, respectively. The most common complication was pseudocyst and abscess and it presented in 21 (20%) patients and their CTSI was 5.9+/-1.4. A CTSI > or =5 significantly correlated with death, complication present, and prolonged length of stay. Patients with a CTSI > or =5 were 15 times to die than those CTSI <5, and the prolonged length of stay and complications present were 17 times and 8 times than that in CTSI <5, respectively. CONCLUSION: CTSI is a useful tool in assessing the severity and outcome of AP and the CTSI > or =5 is an index in our study. Although Ranson score and APACHE II score also are choices to be the predictors for complications, mortality and the length of stay of AP, the sensitivity of them are lower than CTSI.

APACHE↗
PubMed2005

Difficulty with diagnosis of malignant pancreatic neoplasms coexisting with chronic pancreatitis.

Chronic pancreatitis is a relatively common disease. We encountered two different cases of belatedly demonstrated pancreatic carcinoma featuring underlying chronic pancreatitis. The first case was one that was highly suspected as that of a malignancy based upon imaging study, but unfortunately, it could not be confirmed by intra-operative cytology at that time. Following this, the surgeon elected to perform only conservative bypass surgery for obstructive biliary complication. Peritoneal carcinomatosis was later noted and the patient finally died. The second case, a malignant mucinous neoplasm, was falsely diagnosed as a pseudocyst, based upon the lesion's sonographic appearance and associated elevated serum amylase levels. After suffering repeated hemoptysis, the patient was found to exhibit lung metastasis and peritoneal seeding. We reviewed some of the literature, including those studies discussing chronic pancreatitis predisposing to a malignant change. These two case analyses illustrate clearly that the diagnosis for such conditions, which is simply based upon imagery or pathological considerations may end up being one of a mistaken malignancy. Some of our suggestions for the treatment of such malignancies as revealed herein include, total pancreatomy for univocal mass lesion, and needle aspiration of lesion-contained tissue for amylase, CA199 and CEA levels for a suspicious cystic pancreatic mass.

Chronic Disease↗
PubMed2005

Post-radiation survival time in hepatocellular carcinoma based on predictors for CT-determined, transarterial embolization and various other parameters.

AIM: In this retrospective study of unresectable hepatocellular carcinoma (HCC), we have investigated the efficacy of CT-derived parameters, laboratory measurements, clinical assessment and associated transarterial embolization (TAE) as predictors of post-radiotherapy survival time. METHODS: Sixty-six patients diagnosed with unresectable HCC that had undergone radiotherapy at two medical university hospitals in Taipei were enrolled in the study. Using multivariant analysis, pre-treatment parameters including tumor number and CT confirmation of PVT and ascites were compared. Multivariant analysis was also used for comparison of the mean pretreatment values for laboratory measurements, including alpha-fetoprotein, direct/total bilirubin and GOT/GPT levels, and clinical history of chronic hepatitis across the three survival-time categories. The chi2 was used to test the significance of the relationship between survival time and TAE procedure. The P values for the above tests were deemed statistically significant where P<0.05. RESULTS: Portal vein thrombosis (P = 0.032) and ascites (P<0.05) were negative predictors of post-radiation survival time. Low-grade liver cirrhosis (A or B), lower tumor volume and low levels of AFT, GOT/GPT, and total bilirubin were predictors of longer post-radiation survival time (P<0.05). CONCLUSION: The CT and clinical and laboratory assessment provide a reference for, and enable estimation of, probable survival times in HCC patients after radiotherapy. Tumor volume, severity of liver cirrhosis, status with respect to portal vein thrombosis and ascites and AFT, GOT/GPT and total bilirubin values were significant predictors of survival in this study.

Ascites↗
PubMed2005

Anatomic and technical skill factor of gastroduodenal complication in post-transarterial embolization for hepatocellular carcinoma: a retrospective study of 280 cases.

AIM: To reduce the possibility of gastroduodenal complications. The purpose of this retrospective study was to survey the literature and compare and discuss the incidence of post-transarterial embolization (TAE) gastroduodenal complications. METHODS: We found reports describing 280 cases of hepatocellular carcinoma with TAE procedures done during the past 4 years and selected all of them for our study. Amongst these cases, 86 were suspected of suffering gastroduodenal complications within one month of post-TAE treatment. Fifteen of these cases were proved by pan-endoscopy to have gastroduodenal erosions or ulcerations. We reviewed the angiographic pictures in patient records to evaluate the possibility that anatomic and technical skill factors could explain the complications. RESULTS: Amongst the 15 cases, 9 were primary lesions of the antrum and prepylorus; 4 had duodenal ulcer or erosions; 2 had mid-body lesions; none showed a lesion at the fundus or cardia region. Three cases had not received TAEs using our ideal method, and may be associated with possible regurgitation of gel-foam pieces into the right or left gastric arteries. Two cases involved sub-selective embolization at a distal point on the hepatic artery; one case was found by angiography to have complete occlusion of the celiac trunk. CONCLUSION: Comparing our results with past cases of post-TAE gastroduodenal complications, we surmise that our relatively low incidence (5.3%) of gastric complications might be explained by our concerted efforts to improve our technical skills in multi-sequential, selective and super-selective approaches to the embolization of tumor vessels.

Abdomen↗
PubMed2004

Gastrointestinal stromal tumor: Computed tomographic features.

AIM: Gastrointestinal stromal tumor (GIST) is a rare type of cancer. Computed tomography (CT) is an imaging modality of choice for diagnosing GIST. The aim of this retrospective study was to review the CT imaging features of 17 GIST patients. METHODS: From 1995 to 2003, there were 47 patients with pathologically proven GISTs at our hospital. Of these, 17 patients underwent preoperative CT. We collected and analyzed these CT images. The CT imaging features included tumor diameter, number and location, tumor margin, location of metastasis, hounsfield units of tumor and effect of contrasts. In addition, we also recorded the surgical findings, including complications, tumor size and location for comparative analysis. RESULTS: The results showed that 12 (70%) tumors were located in the stomach and five (30%) were located in the jejunum mesentery. GISTs were extraluminal in 12 (70%) patients. The tumor margins of 13 (76%) tumors were well defined and irregular in four (24%). The effect of contrast enhancement on GIST CT imaging was homogenous enhancement in 13 (76%) and heterogeneous enhancement in four (24%). The hounsfield units (HU) were 30.41 +/-5.01 for precontrast images and postcontrast hounsfield units were 51.80 +/- 9.24. CONCLUSION: The stomach was the commonest site of GIST occurrence among our patients. The CT features of GIST were well-defined tumor margins, homogenous enhancement on postcontrast CT images.

Adult↗
PubMed2004

Magnetic resonance cholangiopancreatography of anatomic variants of the biliary tree in Taiwanese.

BACKGROUND AND PURPOSE: Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive method for evaluating the hepatobiliary system. This study investigated the anatomic variants of the biliary tree in Taiwanese using MRCP. METHODS: 170 patients with abdominal or liver diseases underwent diagnostic MRCP over the 29-month study period. We identified the type of biliary tree variants in 130 patients. RESULTS: The imaging findings showed that the most common biliary tree variants were type I and type IIA, which together comprised 70% of all variants. Type I is a triple confluence, which is an anatomy characterized by simultaneous emptying of the right posterior segment duct, right anterior segment duct, and left hepatic duct into the common hepatic duct. Type IIA involves drainage of the right posterior segment duct into the right anterior segment duct to form the right hepatic duct, and then confluence with the left hepatic duct to form the common hepatic duct. There was a mean percentage of 10 to 20% among the 7 types of variants identified. CONCLUSION: Comparison of these findings with previous investigation indicates that biliary tract structure shows racial and ethnic variation.

Bile Ducts↗
PubMed2003

Imaging of renal tuberculosis in eastern Taiwan: correlation with clinical course and different communities.

Hualien, located in eastern Taiwan, is a relatively isolated district. The population is composed of different ethnic communities. Our hospital is the only medical center in eastern Taiwan, so is the most important referral hospital for epidemic diseases. After reviewing our collected cases of renal tuberculosis (TB), we observed a great diversity in staging and outcomes. The aim of this study was to classify different imaging presentations and clinical outcomes in the ethnic communities represented by these cases (non-aboriginal and aboriginal). We retrospectively reviewed 22 cases from 1991 to 2001. We reviewed laboratory data, radiologic reports, and clinical outcomes. Before TB was proved by biopsy or culture, patients were not treated with an anti-TB regimen. Roentgenography showed that 68% of patients had renal calcification, 59% had dilated calyces, 55% had lung involvement, and 41% had auto-nephrectomy. The proportion of mild and severe forms was significantly different between aboriginal and non-aboriginal groups (0.05 > p > or = 0.00409). From this series, we recommend routine plain film roentgenography, including chest roentgenography and kidney, ureter, and bladder or abdominal roentgenography, followed by intravenous urography or computerized tomography as investigative tools for renal TB. Based on the significantly different outcomes of the disease between aboriginal and non-aboriginal groups, a stronger health education program for the isolated district in eastern Taiwan is necessary.

Antitubercular Agents↗
PubMedDate not supplied

Double guidewire method: a novel technique for correction of migrated Tenckhoff peritoneal dialysis catheter.

Twenty-two consecutive patients with a continuous ambulatory peritoneal dialysis (CAPD) catheter malfunctioning due to catheter migration were treated with a novel radiological manipulation technique, the "double guidewire method." The first guidewire is used to correct the direction of the catheter tip and the second wire is used to anchor the CAPD catheter so that an ideal course of the catheter can be maintained during removal of the first guidewire. Immediate catheter repositioning was achieved in 19 of 22 patients, and durable repositioning success was achieved in 13 patients. In conclusion, the "double guidewire method" is a simple but effective technique for prolonging CAPD catheter life in patients with malfunction due to catheter migration.

Adult↗